Series hybrid vehicles and parallel hybrid vehicles are known as hybrid vehicles. Series hybrid vehicles use an engine for power generation only, while parallel hybrid vehicles utilize the driving power of the engine even for traveling.
Series hybrid vehicles do not utilize the driving power of the engine directly for traveling, and therefore, they have limited traveling modes compared to parallel hybrid vehicles.
Patent Document 1 discloses controlling power generation such that a secondary battery of a series hybrid vehicle has a higher target SOC value during high-speed traveling than during low-speed traveling. It is thus possible to obtain sufficient driving power even during high-speed traveling as energy for enabling traveling even under a continuous high load.